dt-bindings: phy: convert phy-mvebu-utmi to YAML schema

The new file name is marvell,armada-3700-utmi-phy.yaml

Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210307163343.25684-3-kostap@marvell.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>